Genetic characterization of the Mirgorod pig breed, obtained by analysis of single nucleotide polymorphisms of genes

Abstract

Aim. To determine genetic characteristics of the Mirgorod pig breed by analysis of 25 SNPs of 22 genes and to conduct the associative analysis of genes MC4R (SNP c.1426 G > A), LEP (SNP g.2845 А ˃ Т), GH (BsuRI- polymorphism), CTSF (SNP g. 22 G > C) with productive traits of animals. Methods. Blood samples of pedigree Mirgorod pigs, bred at SI «Experimental farm named after Decemberists», Poltava region, were used for the studies. DNA genotyping was performed by PCR-RFLP and TaqMan. Results. Specifi c features of the breed were determined in terms of gene allele frequencies, high level of genetic variability (He – 0.326) and allelic diversity (mean number of alleles per locus – 1.96). The KPL2/m allele that causes genetic anomaly of ISTS is absent among investigated Mirgorod pigs, and the recessive RYR1 g.1843T allele, responsible for stress sensitivity of pigs, occurs at a low frequency (0.04). Unlike other breeds, a relatively high frequency of the minor allele g.15A (0.16) of CTSK and polymorphism of the LEP gene (SNP g.3996 T > C) (He – 0.455) was observed. Statistically signifi cant associations of polymorphisms have been established: MC4R (SNP c.1426 G > A) with age of gaining 100 kg, the thickness of backfat and the Eye Muscle Area, GH/BsuRI with the age of gaining 100 kg, and CTSF (SNP g. 22G > C) with Eye Muscle Area. There was a trend of statistically signifi cant differences between groups of pigs with different genotypes of LEP (SNP g.2845 А ˃ Т) and the thickness of the backfat (p = 0.09). Conclusions. It is reasonable to carry out the restoration of the gene pool of the Mirgorod pig breed, taking into account the SNPs of the studied genes and their associations with the productive traits. It is expedient to give preference to pigs with SNP genotypes с.1426 MC4R GA, MC4R AA, g. 22 CTSF CC, g.2845 LEP TT for breed reproduction.